1. Technical Field
The present disclosure relates to an etching composition and/or a method for fabricating a semiconductor device by using the same, and more particularly, to an etching composition provided to selectively remove silicon-germanium from a stack structure including a silicon film and a silicon-germanium film, and a method for fabricating a semiconductor device by using the same.
2. Description of Related Art
The recent dramatic increase in the distribution of information media has led into remarkable advancement in the functionalities of semiconductor devices. To ensure higher competitiveness, new semiconductor products are being developed to meet demands for lower cost and higher quality by way of higher integration. The semiconductor scale-down continues to achieve higher integration.
For semiconductor device density enhancement, the gate-all-around structure has been suggested as one of the scaling technologies, according to which a silicon body in a nanowire shape is formed on a substrate, with a gate then being formed to surround the silicon body.
Meanwhile, in wet process of a method for fabricating a semiconductor device, hydrofluoric acid or mixture solution of hydrofluoric acid and ammonium fluoride may be used for the purpose of cleaning and etching a silicon oxide film, a silicon-germanium thin film, a gallium arsenide thin film, and so on.
Further, because the next generation semiconductor device fabricating process continuously miniaturizes the semiconductor device, there is interest in developing an etching composition for a wet process that has a high etch selectivity with respect to a thin film material. One etching composition, as described in Korean Publication Patent No. 1991-0006458, to optimize a chemical composition of hydrofluoric acid and ammonium fluoride for efficiently etching a semiconductor silicon film has been used in the semiconductor device fabricating process.
However, the existing etching composition has a shortcoming for etch selectivity between a polysilicon film and a SiGe film (where, etch selectivity is obtained by dividing etch rate of SiGe by etch rate of the polysilicon film).